1 /* 2 * QEMU TX packets abstractions 3 * 4 * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com) 5 * 6 * Developed by Daynix Computing LTD (http://www.daynix.com) 7 * 8 * Authors: 9 * Dmitry Fleytman <dmitry@daynix.com> 10 * Tamir Shomer <tamirs@daynix.com> 11 * Yan Vugenfirer <yan@daynix.com> 12 * 13 * This work is licensed under the terms of the GNU GPL, version 2 or later. 14 * See the COPYING file in the top-level directory. 15 * 16 */ 17 18 #include "qemu/osdep.h" 19 #include "net_tx_pkt.h" 20 #include "net/eth.h" 21 #include "net/checksum.h" 22 #include "net/tap.h" 23 #include "net/net.h" 24 #include "hw/pci/pci_device.h" 25 26 enum { 27 NET_TX_PKT_VHDR_FRAG = 0, 28 NET_TX_PKT_L2HDR_FRAG, 29 NET_TX_PKT_L3HDR_FRAG, 30 NET_TX_PKT_PL_START_FRAG 31 }; 32 33 /* TX packet private context */ 34 struct NetTxPkt { 35 PCIDevice *pci_dev; 36 37 struct virtio_net_hdr virt_hdr; 38 bool has_virt_hdr; 39 40 struct iovec *raw; 41 uint32_t raw_frags; 42 uint32_t max_raw_frags; 43 44 struct iovec *vec; 45 46 uint8_t l2_hdr[ETH_MAX_L2_HDR_LEN]; 47 uint8_t l3_hdr[ETH_MAX_IP_DGRAM_LEN]; 48 49 uint32_t payload_len; 50 51 uint32_t payload_frags; 52 uint32_t max_payload_frags; 53 54 uint16_t hdr_len; 55 eth_pkt_types_e packet_type; 56 uint8_t l4proto; 57 58 bool is_loopback; 59 }; 60 61 void net_tx_pkt_init(struct NetTxPkt **pkt, PCIDevice *pci_dev, 62 uint32_t max_frags, bool has_virt_hdr) 63 { 64 struct NetTxPkt *p = g_malloc0(sizeof *p); 65 66 p->pci_dev = pci_dev; 67 68 p->vec = g_new(struct iovec, max_frags + NET_TX_PKT_PL_START_FRAG); 69 70 p->raw = g_new(struct iovec, max_frags); 71 72 p->max_payload_frags = max_frags; 73 p->max_raw_frags = max_frags; 74 p->has_virt_hdr = has_virt_hdr; 75 p->vec[NET_TX_PKT_VHDR_FRAG].iov_base = &p->virt_hdr; 76 p->vec[NET_TX_PKT_VHDR_FRAG].iov_len = 77 p->has_virt_hdr ? sizeof p->virt_hdr : 0; 78 p->vec[NET_TX_PKT_L2HDR_FRAG].iov_base = &p->l2_hdr; 79 p->vec[NET_TX_PKT_L3HDR_FRAG].iov_base = &p->l3_hdr; 80 81 *pkt = p; 82 } 83 84 void net_tx_pkt_uninit(struct NetTxPkt *pkt) 85 { 86 if (pkt) { 87 g_free(pkt->vec); 88 g_free(pkt->raw); 89 g_free(pkt); 90 } 91 } 92 93 void net_tx_pkt_update_ip_hdr_checksum(struct NetTxPkt *pkt) 94 { 95 uint16_t csum; 96 assert(pkt); 97 struct ip_header *ip_hdr; 98 ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 99 100 ip_hdr->ip_len = cpu_to_be16(pkt->payload_len + 101 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); 102 103 ip_hdr->ip_sum = 0; 104 csum = net_raw_checksum((uint8_t *)ip_hdr, 105 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); 106 ip_hdr->ip_sum = cpu_to_be16(csum); 107 } 108 109 void net_tx_pkt_update_ip_checksums(struct NetTxPkt *pkt) 110 { 111 uint16_t csum; 112 uint32_t cntr, cso; 113 assert(pkt); 114 uint8_t gso_type = pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN; 115 void *ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 116 117 if (pkt->payload_len + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len > 118 ETH_MAX_IP_DGRAM_LEN) { 119 return; 120 } 121 122 if (gso_type == VIRTIO_NET_HDR_GSO_TCPV4 || 123 gso_type == VIRTIO_NET_HDR_GSO_UDP) { 124 /* Calculate IP header checksum */ 125 net_tx_pkt_update_ip_hdr_checksum(pkt); 126 127 /* Calculate IP pseudo header checksum */ 128 cntr = eth_calc_ip4_pseudo_hdr_csum(ip_hdr, pkt->payload_len, &cso); 129 csum = cpu_to_be16(~net_checksum_finish(cntr)); 130 } else if (gso_type == VIRTIO_NET_HDR_GSO_TCPV6) { 131 /* Calculate IP pseudo header checksum */ 132 cntr = eth_calc_ip6_pseudo_hdr_csum(ip_hdr, pkt->payload_len, 133 IP_PROTO_TCP, &cso); 134 csum = cpu_to_be16(~net_checksum_finish(cntr)); 135 } else { 136 return; 137 } 138 139 iov_from_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], pkt->payload_frags, 140 pkt->virt_hdr.csum_offset, &csum, sizeof(csum)); 141 } 142 143 static void net_tx_pkt_calculate_hdr_len(struct NetTxPkt *pkt) 144 { 145 pkt->hdr_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len + 146 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; 147 } 148 149 static bool net_tx_pkt_parse_headers(struct NetTxPkt *pkt) 150 { 151 struct iovec *l2_hdr, *l3_hdr; 152 size_t bytes_read; 153 size_t full_ip6hdr_len; 154 uint16_t l3_proto; 155 156 assert(pkt); 157 158 l2_hdr = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 159 l3_hdr = &pkt->vec[NET_TX_PKT_L3HDR_FRAG]; 160 161 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, 0, l2_hdr->iov_base, 162 ETH_MAX_L2_HDR_LEN); 163 if (bytes_read < sizeof(struct eth_header)) { 164 l2_hdr->iov_len = 0; 165 return false; 166 } 167 168 l2_hdr->iov_len = sizeof(struct eth_header); 169 switch (be16_to_cpu(PKT_GET_ETH_HDR(l2_hdr->iov_base)->h_proto)) { 170 case ETH_P_VLAN: 171 l2_hdr->iov_len += sizeof(struct vlan_header); 172 break; 173 case ETH_P_DVLAN: 174 l2_hdr->iov_len += 2 * sizeof(struct vlan_header); 175 break; 176 } 177 178 if (bytes_read < l2_hdr->iov_len) { 179 l2_hdr->iov_len = 0; 180 l3_hdr->iov_len = 0; 181 pkt->packet_type = ETH_PKT_UCAST; 182 return false; 183 } else { 184 l2_hdr->iov_len = ETH_MAX_L2_HDR_LEN; 185 l2_hdr->iov_len = eth_get_l2_hdr_length(l2_hdr->iov_base); 186 pkt->packet_type = get_eth_packet_type(l2_hdr->iov_base); 187 } 188 189 l3_proto = eth_get_l3_proto(l2_hdr, 1, l2_hdr->iov_len); 190 191 switch (l3_proto) { 192 case ETH_P_IP: 193 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 194 l3_hdr->iov_base, sizeof(struct ip_header)); 195 196 if (bytes_read < sizeof(struct ip_header)) { 197 l3_hdr->iov_len = 0; 198 return false; 199 } 200 201 l3_hdr->iov_len = IP_HDR_GET_LEN(l3_hdr->iov_base); 202 203 if (l3_hdr->iov_len < sizeof(struct ip_header)) { 204 l3_hdr->iov_len = 0; 205 return false; 206 } 207 208 pkt->l4proto = IP_HDR_GET_P(l3_hdr->iov_base); 209 210 if (IP_HDR_GET_LEN(l3_hdr->iov_base) != sizeof(struct ip_header)) { 211 /* copy optional IPv4 header data if any*/ 212 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, 213 l2_hdr->iov_len + sizeof(struct ip_header), 214 l3_hdr->iov_base + sizeof(struct ip_header), 215 l3_hdr->iov_len - sizeof(struct ip_header)); 216 if (bytes_read < l3_hdr->iov_len - sizeof(struct ip_header)) { 217 l3_hdr->iov_len = 0; 218 return false; 219 } 220 } 221 222 break; 223 224 case ETH_P_IPV6: 225 { 226 eth_ip6_hdr_info hdrinfo; 227 228 if (!eth_parse_ipv6_hdr(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 229 &hdrinfo)) { 230 l3_hdr->iov_len = 0; 231 return false; 232 } 233 234 pkt->l4proto = hdrinfo.l4proto; 235 full_ip6hdr_len = hdrinfo.full_hdr_len; 236 237 if (full_ip6hdr_len > ETH_MAX_IP_DGRAM_LEN) { 238 l3_hdr->iov_len = 0; 239 return false; 240 } 241 242 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 243 l3_hdr->iov_base, full_ip6hdr_len); 244 245 if (bytes_read < full_ip6hdr_len) { 246 l3_hdr->iov_len = 0; 247 return false; 248 } else { 249 l3_hdr->iov_len = full_ip6hdr_len; 250 } 251 break; 252 } 253 default: 254 l3_hdr->iov_len = 0; 255 break; 256 } 257 258 net_tx_pkt_calculate_hdr_len(pkt); 259 return true; 260 } 261 262 static void net_tx_pkt_rebuild_payload(struct NetTxPkt *pkt) 263 { 264 pkt->payload_len = iov_size(pkt->raw, pkt->raw_frags) - pkt->hdr_len; 265 pkt->payload_frags = iov_copy(&pkt->vec[NET_TX_PKT_PL_START_FRAG], 266 pkt->max_payload_frags, 267 pkt->raw, pkt->raw_frags, 268 pkt->hdr_len, pkt->payload_len); 269 } 270 271 bool net_tx_pkt_parse(struct NetTxPkt *pkt) 272 { 273 if (net_tx_pkt_parse_headers(pkt)) { 274 net_tx_pkt_rebuild_payload(pkt); 275 return true; 276 } else { 277 return false; 278 } 279 } 280 281 struct virtio_net_hdr *net_tx_pkt_get_vhdr(struct NetTxPkt *pkt) 282 { 283 assert(pkt); 284 return &pkt->virt_hdr; 285 } 286 287 static uint8_t net_tx_pkt_get_gso_type(struct NetTxPkt *pkt, 288 bool tso_enable) 289 { 290 uint8_t rc = VIRTIO_NET_HDR_GSO_NONE; 291 uint16_t l3_proto; 292 293 l3_proto = eth_get_l3_proto(&pkt->vec[NET_TX_PKT_L2HDR_FRAG], 1, 294 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len); 295 296 if (!tso_enable) { 297 goto func_exit; 298 } 299 300 rc = eth_get_gso_type(l3_proto, pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 301 pkt->l4proto); 302 303 func_exit: 304 return rc; 305 } 306 307 bool net_tx_pkt_build_vheader(struct NetTxPkt *pkt, bool tso_enable, 308 bool csum_enable, uint32_t gso_size) 309 { 310 struct tcp_hdr l4hdr; 311 size_t bytes_read; 312 assert(pkt); 313 314 /* csum has to be enabled if tso is. */ 315 assert(csum_enable || !tso_enable); 316 317 pkt->virt_hdr.gso_type = net_tx_pkt_get_gso_type(pkt, tso_enable); 318 319 switch (pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 320 case VIRTIO_NET_HDR_GSO_NONE: 321 pkt->virt_hdr.hdr_len = 0; 322 pkt->virt_hdr.gso_size = 0; 323 break; 324 325 case VIRTIO_NET_HDR_GSO_UDP: 326 pkt->virt_hdr.gso_size = gso_size; 327 pkt->virt_hdr.hdr_len = pkt->hdr_len + sizeof(struct udp_header); 328 break; 329 330 case VIRTIO_NET_HDR_GSO_TCPV4: 331 case VIRTIO_NET_HDR_GSO_TCPV6: 332 bytes_read = iov_to_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], 333 pkt->payload_frags, 0, &l4hdr, sizeof(l4hdr)); 334 if (bytes_read < sizeof(l4hdr)) { 335 return false; 336 } 337 338 pkt->virt_hdr.hdr_len = pkt->hdr_len + l4hdr.th_off * sizeof(uint32_t); 339 pkt->virt_hdr.gso_size = gso_size; 340 break; 341 342 default: 343 g_assert_not_reached(); 344 } 345 346 if (csum_enable) { 347 switch (pkt->l4proto) { 348 case IP_PROTO_TCP: 349 pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 350 pkt->virt_hdr.csum_start = pkt->hdr_len; 351 pkt->virt_hdr.csum_offset = offsetof(struct tcp_hdr, th_sum); 352 break; 353 case IP_PROTO_UDP: 354 pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 355 pkt->virt_hdr.csum_start = pkt->hdr_len; 356 pkt->virt_hdr.csum_offset = offsetof(struct udp_hdr, uh_sum); 357 break; 358 default: 359 break; 360 } 361 } 362 363 return true; 364 } 365 366 void net_tx_pkt_setup_vlan_header_ex(struct NetTxPkt *pkt, 367 uint16_t vlan, uint16_t vlan_ethtype) 368 { 369 bool is_new; 370 assert(pkt); 371 372 eth_setup_vlan_headers_ex(pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base, 373 vlan, vlan_ethtype, &is_new); 374 375 /* update l2hdrlen */ 376 if (is_new) { 377 pkt->hdr_len += sizeof(struct vlan_header); 378 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len += 379 sizeof(struct vlan_header); 380 } 381 } 382 383 bool net_tx_pkt_add_raw_fragment(struct NetTxPkt *pkt, hwaddr pa, 384 size_t len) 385 { 386 hwaddr mapped_len = 0; 387 struct iovec *ventry; 388 assert(pkt); 389 390 if (pkt->raw_frags >= pkt->max_raw_frags) { 391 return false; 392 } 393 394 if (!len) { 395 return true; 396 } 397 398 ventry = &pkt->raw[pkt->raw_frags]; 399 mapped_len = len; 400 401 ventry->iov_base = pci_dma_map(pkt->pci_dev, pa, 402 &mapped_len, DMA_DIRECTION_TO_DEVICE); 403 404 if ((ventry->iov_base != NULL) && (len == mapped_len)) { 405 ventry->iov_len = mapped_len; 406 pkt->raw_frags++; 407 return true; 408 } else { 409 return false; 410 } 411 } 412 413 bool net_tx_pkt_has_fragments(struct NetTxPkt *pkt) 414 { 415 return pkt->raw_frags > 0; 416 } 417 418 eth_pkt_types_e net_tx_pkt_get_packet_type(struct NetTxPkt *pkt) 419 { 420 assert(pkt); 421 422 return pkt->packet_type; 423 } 424 425 size_t net_tx_pkt_get_total_len(struct NetTxPkt *pkt) 426 { 427 assert(pkt); 428 429 return pkt->hdr_len + pkt->payload_len; 430 } 431 432 void net_tx_pkt_dump(struct NetTxPkt *pkt) 433 { 434 #ifdef NET_TX_PKT_DEBUG 435 assert(pkt); 436 437 printf("TX PKT: hdr_len: %d, pkt_type: 0x%X, l2hdr_len: %lu, " 438 "l3hdr_len: %lu, payload_len: %u\n", pkt->hdr_len, pkt->packet_type, 439 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len, 440 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len, pkt->payload_len); 441 #endif 442 } 443 444 void net_tx_pkt_reset(struct NetTxPkt *pkt) 445 { 446 int i; 447 448 /* no assert, as reset can be called before tx_pkt_init */ 449 if (!pkt) { 450 return; 451 } 452 453 memset(&pkt->virt_hdr, 0, sizeof(pkt->virt_hdr)); 454 455 assert(pkt->vec); 456 457 pkt->payload_len = 0; 458 pkt->payload_frags = 0; 459 460 if (pkt->max_raw_frags > 0) { 461 assert(pkt->raw); 462 for (i = 0; i < pkt->raw_frags; i++) { 463 assert(pkt->raw[i].iov_base); 464 pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, 465 pkt->raw[i].iov_len, DMA_DIRECTION_TO_DEVICE, 0); 466 } 467 } 468 pkt->raw_frags = 0; 469 470 pkt->hdr_len = 0; 471 pkt->l4proto = 0; 472 } 473 474 static void net_tx_pkt_do_sw_csum(struct NetTxPkt *pkt) 475 { 476 struct iovec *iov = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 477 uint32_t csum_cntr; 478 uint16_t csum = 0; 479 uint32_t cso; 480 /* num of iovec without vhdr */ 481 uint32_t iov_len = pkt->payload_frags + NET_TX_PKT_PL_START_FRAG - 1; 482 uint16_t csl; 483 size_t csum_offset = pkt->virt_hdr.csum_start + pkt->virt_hdr.csum_offset; 484 uint16_t l3_proto = eth_get_l3_proto(iov, 1, iov->iov_len); 485 486 /* Put zero to checksum field */ 487 iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); 488 489 /* Calculate L4 TCP/UDP checksum */ 490 csl = pkt->payload_len; 491 492 csum_cntr = 0; 493 cso = 0; 494 /* add pseudo header to csum */ 495 if (l3_proto == ETH_P_IP) { 496 csum_cntr = eth_calc_ip4_pseudo_hdr_csum( 497 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 498 csl, &cso); 499 } else if (l3_proto == ETH_P_IPV6) { 500 csum_cntr = eth_calc_ip6_pseudo_hdr_csum( 501 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 502 csl, pkt->l4proto, &cso); 503 } 504 505 /* data checksum */ 506 csum_cntr += 507 net_checksum_add_iov(iov, iov_len, pkt->virt_hdr.csum_start, csl, cso); 508 509 /* Put the checksum obtained into the packet */ 510 csum = cpu_to_be16(net_checksum_finish_nozero(csum_cntr)); 511 iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); 512 } 513 514 enum { 515 NET_TX_PKT_FRAGMENT_L2_HDR_POS = 0, 516 NET_TX_PKT_FRAGMENT_L3_HDR_POS, 517 NET_TX_PKT_FRAGMENT_HEADER_NUM 518 }; 519 520 #define NET_MAX_FRAG_SG_LIST (64) 521 522 static size_t net_tx_pkt_fetch_fragment(struct NetTxPkt *pkt, 523 int *src_idx, size_t *src_offset, struct iovec *dst, int *dst_idx) 524 { 525 size_t fetched = 0; 526 struct iovec *src = pkt->vec; 527 528 *dst_idx = NET_TX_PKT_FRAGMENT_HEADER_NUM; 529 530 while (fetched < IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size)) { 531 532 /* no more place in fragment iov */ 533 if (*dst_idx == NET_MAX_FRAG_SG_LIST) { 534 break; 535 } 536 537 /* no more data in iovec */ 538 if (*src_idx == (pkt->payload_frags + NET_TX_PKT_PL_START_FRAG)) { 539 break; 540 } 541 542 543 dst[*dst_idx].iov_base = src[*src_idx].iov_base + *src_offset; 544 dst[*dst_idx].iov_len = MIN(src[*src_idx].iov_len - *src_offset, 545 IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size) - fetched); 546 547 *src_offset += dst[*dst_idx].iov_len; 548 fetched += dst[*dst_idx].iov_len; 549 550 if (*src_offset == src[*src_idx].iov_len) { 551 *src_offset = 0; 552 (*src_idx)++; 553 } 554 555 (*dst_idx)++; 556 } 557 558 return fetched; 559 } 560 561 static inline void net_tx_pkt_sendv(struct NetTxPkt *pkt, 562 NetClientState *nc, const struct iovec *iov, int iov_cnt) 563 { 564 if (pkt->is_loopback) { 565 qemu_receive_packet_iov(nc, iov, iov_cnt); 566 } else { 567 qemu_sendv_packet(nc, iov, iov_cnt); 568 } 569 } 570 571 static bool net_tx_pkt_do_sw_fragmentation(struct NetTxPkt *pkt, 572 NetClientState *nc) 573 { 574 struct iovec fragment[NET_MAX_FRAG_SG_LIST]; 575 size_t fragment_len = 0; 576 bool more_frags = false; 577 578 /* some pointers for shorter code */ 579 void *l2_iov_base, *l3_iov_base; 580 size_t l2_iov_len, l3_iov_len; 581 int src_idx = NET_TX_PKT_PL_START_FRAG, dst_idx; 582 size_t src_offset = 0; 583 size_t fragment_offset = 0; 584 585 l2_iov_base = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base; 586 l2_iov_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len; 587 l3_iov_base = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 588 l3_iov_len = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; 589 590 /* Copy headers */ 591 fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_base = l2_iov_base; 592 fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_len = l2_iov_len; 593 fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_base = l3_iov_base; 594 fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_len = l3_iov_len; 595 596 597 /* Put as much data as possible and send */ 598 do { 599 fragment_len = net_tx_pkt_fetch_fragment(pkt, &src_idx, &src_offset, 600 fragment, &dst_idx); 601 602 more_frags = (fragment_offset + fragment_len < pkt->payload_len); 603 604 eth_setup_ip4_fragmentation(l2_iov_base, l2_iov_len, l3_iov_base, 605 l3_iov_len, fragment_len, fragment_offset, more_frags); 606 607 eth_fix_ip4_checksum(l3_iov_base, l3_iov_len); 608 609 net_tx_pkt_sendv(pkt, nc, fragment, dst_idx); 610 611 fragment_offset += fragment_len; 612 613 } while (fragment_len && more_frags); 614 615 return true; 616 } 617 618 bool net_tx_pkt_send(struct NetTxPkt *pkt, NetClientState *nc) 619 { 620 assert(pkt); 621 622 if (!pkt->has_virt_hdr && 623 pkt->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 624 net_tx_pkt_do_sw_csum(pkt); 625 } 626 627 /* 628 * Since underlying infrastructure does not support IP datagrams longer 629 * than 64K we should drop such packets and don't even try to send 630 */ 631 if (VIRTIO_NET_HDR_GSO_NONE != pkt->virt_hdr.gso_type) { 632 if (pkt->payload_len > 633 ETH_MAX_IP_DGRAM_LEN - 634 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len) { 635 return false; 636 } 637 } 638 639 if (pkt->has_virt_hdr || 640 pkt->virt_hdr.gso_type == VIRTIO_NET_HDR_GSO_NONE) { 641 net_tx_pkt_fix_ip6_payload_len(pkt); 642 net_tx_pkt_sendv(pkt, nc, pkt->vec, 643 pkt->payload_frags + NET_TX_PKT_PL_START_FRAG); 644 return true; 645 } 646 647 return net_tx_pkt_do_sw_fragmentation(pkt, nc); 648 } 649 650 bool net_tx_pkt_send_loopback(struct NetTxPkt *pkt, NetClientState *nc) 651 { 652 bool res; 653 654 pkt->is_loopback = true; 655 res = net_tx_pkt_send(pkt, nc); 656 pkt->is_loopback = false; 657 658 return res; 659 } 660 661 void net_tx_pkt_fix_ip6_payload_len(struct NetTxPkt *pkt) 662 { 663 struct iovec *l2 = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 664 if (eth_get_l3_proto(l2, 1, l2->iov_len) == ETH_P_IPV6) { 665 struct ip6_header *ip6 = (struct ip6_header *) pkt->l3_hdr; 666 /* 667 * TODO: if qemu would support >64K packets - add jumbo option check 668 * something like that: 669 * 'if (ip6->ip6_plen == 0 && !has_jumbo_option(ip6)) {' 670 */ 671 if (ip6->ip6_plen == 0) { 672 if (pkt->payload_len <= ETH_MAX_IP_DGRAM_LEN) { 673 ip6->ip6_plen = htons(pkt->payload_len); 674 } 675 /* 676 * TODO: if qemu would support >64K packets 677 * add jumbo option for packets greater then 65,535 bytes 678 */ 679 } 680 } 681 } 682